Execute a Markov algorithm
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You are encouraged to solve this task according to the task description, using any language you may know.
Create an interpreter for a Markov Algorithm. Rules have the syntax:
<comment> ::= # {<any character>}
<rule> ::= <pattern> <whitespace> -> <whitespace> [.] <replacement>
<whitespace> ::= (<tab> | <space>) [<whitespace>]
There is one rule per line. If there is a . present before the <replacement>, then this is a terminating rule in which case the interpreter must halt execution.
Ruby
<lang Ruby>raise "Please input an input code file, an input data file, and an output file." if ARGV.size < 3
rules = File.readlines(ARGV[0]).map do |line|
if line =~ /^\s*#/
nil
elsif line =~ /^(.+)\s+\-\>\s+(\.?)(.*)$/
[$1, $3, $2 != ""]
else
raise "Syntax error: #{line}"
end
end.delete_if(&:nil?)
File.open(ARGV[2], "w") do |file|
file.write(File.read(ARGV[1]).tap { |input_data|
while rules.find { |match, replace, term|
if input_data[match]
input_data.sub!(match, replace)
break if term
true
else
false
end
}
end
})
end</lang>